Recently there has been much development in the area of portable data storage devices having non-volatile solid state memory units, such as flash memories. A seminal patent application in this area, PCT/SG00/00029, “Portable Data Storage Device”, describes a memory device which can be directly plugged into the socket of a computer using an integral male USB plug. The size of the device is such that it is capable, for example, of being fully enclosed within a closed fist, and is in this sense portable. It is able to receive data from one computer system, and transfer it to another computer system, just like a magnetic disk or CD-RW disk.
Many improvements of this scheme have been proposed. For example, PCT/SG02/00047, describes a portable data storage device in which access to the data in the non-volatile memory device is only permitted to users whose identities have been verified by an integral biometrics sensor, such as a fingerprint sensor.
PCT/SG02/00086 describes that a portable data storage device can include an engine for compressing data and decompressing data, so that the effective data storage capacity of the device (i.e. the amount of typical user data which the device can receive and regenerate) is greater than the nominal capacity of the non-volatile memory device.
Singapore patent application no. 200400358-8 describes a portable data storage device which is adapted for storage of data describing video images, such that the device can be used to a video generation system to play video.
PCT/SG01/00136 describes a portable data storage device which is arranged for wireless communication with a host, e.g. by radio, for receiving data and subsequently regenerating it. The device is thus capable of transferring data between computer systems which are capable of this wireless data transmission. PCT/SG03/00152 describes an enhancement of this system in which the data storage device includes a pointer, so that a user can move it to act as a convenient data input device.
PCT/SG03/00033 describes a portable data storage device which is arranged to receive data securely from an information provider or the Internet. This may use a public key associated with the user and pre-stored in the device.
The disclosure of all of the above references is incorporated herein in its entirety.